Normally the brushes go first or are stuck in the brush holder-so worth a check.
The diodes should be low resistance with the meter leads one way round,and very high resistance when the leads are reversed.
You can test an alternator if you have a battery drill,and you can get the end of the shaft in the drill.Connect a 12volt bulb(indicator) between the big output terminal and ground the other end on the alt body-next you need to connect a 12v battery with the +ve on the field/exciter coil connection (small contact) and then connect the -ve battery to the alt body.Start the drill, the bulb should glow very bright if all is working.
This is a quick way of testing an alt at a breakers,and out of the car.
The diodes should be low resistance with the meter leads one way round,and very high resistance when the leads are reversed.
You can test an alternator if you have a battery drill,and you can get the end of the shaft in the drill.Connect a 12volt bulb(indicator) between the big output terminal and ground the other end on the alt body-next you need to connect a 12v battery with the +ve on the field/exciter coil connection (small contact) and then connect the -ve battery to the alt body.Start the drill, the bulb should glow very bright if all is working.
This is a quick way of testing an alt at a breakers,and out of the car.
sierrafery
Well-Known Member
I ****in give up 
nathan5346
Well-Known Member
£35 fer a recon
I give up posting stuff on here to help ****in idiots that cant be arsed to look. There are at least 6 threads on LZ, one of which is in the FAQ section on how to test alternators.
If peeps cant be arsed to even look before asking a question, I for one cant be arsed to help.
